Particular form of a book (7)
I believe the answer is:
edition
'particular form of a book' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for edition that I've seen before include "in printed form" , "I don tie (anag.)" , "copy of work" , "Copies of book printed from one set of type" , "Something impressed" .)